Typewriting machine



Patented Apr. 30} i I Y i I UNITED, 'STATES PATENT OFFICE TYPEWRITING MACHINE William F. nelmona. West Hartford, Conn., as-

signor to Underwood Elliott Fisher Company, .New York, N. Y., a corporation of Delaware Application February 25, 1931, Serial No. 127,609

8 Claims. icl. 197-102) This invention relates to molded and other type-key stem contracted and the type-key hea solid keys for typewriting machines. The key is partially removed.

made in one piece of Bakelite, Phenolite, Cellu- Figure 3 is a side view of Figure 1. loid, or other suitable material, and preferably Figure 4 is an isometric view of the type-key 6 is dished. For certain purposes the key may he stemattached to the end of the key-lever. 5 molded of soft rubber or other suitable cushion- Figure 5 shows the type-key stem as part of ing material. the key-lever.

An aim of the invention is to dispense with the Figure 6 is an isometric drawing of the typeusual key cup, and also to simplify the construcey em a d typ ey a with parts broken l0 tio'h and reduce the cost of manufacturing and away to show the construction. assembling, and a further aim is to provide for Figure 7 is an isometric drawing of the metal ready attachment and detachment of the key. insert for the type-key head.

The key-stem is a forked resilient member. It gure 8 s a sect Offl yp ey d made may be either a part of the lever, or a separate oi Bakelite or similar material without a metal piece fastened by rivets, welding, or otherwise to i se tv 15 the end of the key-lever. Figure 9 is a sectioned drawing of a Bakelite The forked ends of the stems may be drawn typ y head h a metal inserttogether to allow easy removal or attachment of Figure 10 is a sectioned dr w of a yp y the key. head made of resilient material such as rubber.

2 The upper ends of the key-stems are formed in ure 11 is a sectioned drawing of a silie t two arcs of 90, which curve outwardly. In plan p y headhaving n air c er- 1 these ends appear square or rectangular, with two Figure 12 is a View Of the bot of u e sides contractible inwardly or towards thecenter. ure 13 s a V ew O e to of Figure The key can be easily attached or removed from ur 14 Shows bank of wri eys W 2 the stem, and also will not turn on the stem or a P ir of Pliers in PO t to remove the t? loosen from it. This advantage is gained by 1193i l constructing the key or key-head with a squared The typ-key Stem has t o e t a s d s 2| bottom opening, with two of the sides oi. the an h g the uppe ends two, curved opening undercut and forming a seat into which p r ns 23 and 24, which are curved through fit the curved ends of the key-stem. The'other arcs of shown in Figure he curved 3Q opposite sides are correctly spaced for fittin portions 23 and 24 have rounded endslland 26 tightly againshthe flat sides or the key-stem. for fitting n corresponding rounde surfaces A further *fatilre oftl'ie invention is to provide Z1 d." of the cur d-s s 9 and ot the a metal insert tobe imbedded or inserted into the meta-1 insert 3| ic is imbedde in he ykey head This m g t t f atur above stem head 32. The insert II has twoflat sides 3:, described for-the opening in the b tt of t 33 and 34 which fit against the flat sides or ends key-head, and will prevent chipping or damage 35 of and shown mfigure t t type head when it is being removed or The two vertical sides It and 22 are resiliently tached. Furthermore this insert will permit the held together at h Portion of h use of resilient cushioning material, such as rubstem by back portion of the key'stem her for the h As shownin Figure 4, the key stem 20 may be The rubber key may have a hollow' space or fittedpvefr 3: fi aifi f g is air chamber, to increase the key resilience. n in m ve The cost of making and assembling the key is means 5 8 Own we w are 6 ear-stem II and the key-lever 31 are made of one piece. 415 reduced and the operator is enabled to choose If the kerstem head a is made of Bakelite or keys that most suited to his individual F similar material it may be desirable not to use the at m insert 3|. In such a case the key-stem head 32 Other features and advantages will hereinafter may be made, as shown in Ham-e 3, with rectangular opening II in the bottom of the key- In e accompanying drawing, head 32. Two sides and II of. the opening I! Fi u 1 s a v ew f the d of th t n -k are undercut to at the rounded ends" and It of stem, with the type-key head in place, and in the sides 21 and 22... The other sides 0 are flat section. to flt snugly against the fla't'sides II of the key- 5 Figure z-corresponds to Figure 1 and shows the stem sides 2| and 22. p

either case, the edges 44 may be formed to help hold the insert 3| in place. To get added resilience the rubber key-stem head 32 may be-molded with an air pocket 45, as shown in Figure 11.

The following is a description of how the keystem head 32 may be rigidlyi'lxd to.,the key-stem- 20. Normally the "backing 33 holds the sides 2| and 22 resiliently apart and to attach the keystem button 32, it is first necessary to squeeze the sides 2| and 22 together with a pair of pliers 41 or some other suitable means. When sides 2| and 22 are drawn together the typestem head 32 will flt on as the ends 25 and 28 will clear the sides,23 and 30, and the sides 33 and 33 of insert 3| will position the head 32. When the key-stem sides 2| and 22 are released and allowed to return to their normal position the rounded ends 25 and "will fit into the sides 23 and 30, thereby preventing the head 32 from coming loose. It the Bakelite head 32 is used without an-insert, the

procedure remains the same and therounded,

ends 25 and 26 will fit into the undercut sides 4|! and ll. As the faces 25 and 26 and of the key-stem 20 are at right angles with each other and fit sides 23 and 29.and 33 and 34 of the keystem head 32, which are at right angles with each other, it is impossible for the key-stemhead 32 to turn on the key-stem 23. Variations may be resorted to within the scopeof the invention, and portions of the improvements may be used without others.

\ Having thus described my invention, I claim:

1. The combination with a metal type-key stem having co-extensive resilient members, corresponding end portions of which are directed outwardly at right angles from the members, of a type-key head including a metal plate secured thereto, said plate having opposed marginal portions inturned to closely fit over the end portions of said members, to. securely hold said type-key head releasably on said stem.

2. The combination with a metal type-key stem having co-extensive resilient members, corresponding end portions of which are directed outwardly at right angles from the members, of a type-key head including a rectangular metal plate aflixed thereto, said metal plate having opposed margins inturned to substantially embrace the free ends of said stem-members, the adjoining margins of said plate depending abruptly therefrom'to engage the edges of said stem-members, to securely hold said type-key head releasably on said stem.

v 3. The combination with a metal type-key stemhaving co-extensive resilient members corre-' sponding end portions of which are directed outwardly at right angles from the members, of a type-key head formed of moldable material and having a constricted recess therein, of a metallic member embedded in said type-key head to re iniorce same having 'groove deilning por tions closely fitting over the end portions or saidmembers and merging into, the constricted region of the recess to facilitate removal of the type key head from said stem.

4. The combination with a metal type-key stem having co-exten'sive resilient members corresponding end portions of which turn outwardly at substantial angles from the members, of a fresilient type -key head formed-oi yieldable material and including a. substantially flat metal plate embedded therein, opposed margins'of said plate being inturned to closely fit over the end portions of said stem members for securely holding said type-key head releasably on said stem, said type-key head having a shallow imperforate chamber therein overlying said metal plate, said plate serving'to reinforce an adjacent wall of said chamber against fiexure by impact on the type-key head. 5. A key-lever stem for typewriters and the like, adapted for detachably mounting a key-'" head thereon, the key-head having .prong receiving members, said stem being formed of a single piece of metal and including an offset Portion folded onitself, a part of the fold adjacent the end of said ofiset portion being omitted to present a pair of co-extensive yield-able prongs for releasably engaging the key-head.

6. A key-lever stem for typewriters and the like, adapted for detachably mounting a keyhead thereon, the key-head having prong-receiving members, said stem being formedof a single piece of resilient metal and including an offset portion folded upon itself, a part of the fold adjacent the ends of said offset portion being omitted to present a pair of co-extensive yieldable prongs, the ends 01 said prongs being oppositely. directed for a positive engagement in the prong-receiving members of said key-head.

7. A metal type-key stem having two spaced resilient members with end'portions oppositely "turned outwardly, and a type-key head having a metal plate secured thereto, said plate having opposed marginal portions inturned to closely fit of spring metal of channel formation for a part of its length and presentihga pair of upwardly extending spaced side members, the ends of which provide oppositely directed prongs for. engagement at their tips with said inwardly extending flanges, and for engagement at their side edges with said downwardly extending fianges.

, WILLIAM F. HELMOND. 

